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GPs having to phone patients to find out if they fasted for blood tests

GPs are having to phone patients to find out whether they fasted for their blood tests because blood glucose provenance information is often missing, a study has found. 

Researchers who performed a cross-sectional analysis of blood glucose measurements and a clinical audit in a primary care practice found that provenance information is often missing from glucose tests returned from pathology labs, delaying diabetes diagnosis and causing patients to have unnecessary repeat tests.

The team could not determine what proportion of poor provenance recording originated in the pathology lab or the practice itself but state that ‘general practitioners in our audit practice expressed frustration’.

The lead of the study said they found that GPs were having to phone patients to clarify whether they had fasted for the blood test.

In total, the study - published in Diabetic Medicine - found that 16% of initial glucose tests had to be questioned by a GP, wasting time and delaying diabetes diagnosis – in some cases by more than six months.

The researchers also found that 58% of all glucose tests had provenance information missing and recommend that GPs ensure to record this information on request forms.

Dr Andrew Mcgovern from the University of Surrey, who authored the study, said: ‘The clinical codes already exist to record whether the test was fasted or random but in the majority of cases these codes are not used when the laboratory returns the glucose result.

‘We found that GPs are spending time phoning patients to ask them if they were fasted or not when they had their blood test and in many cases GPs were requesting repeated samples. When requesting and taking blood glucose samples, practitioners should record whether the test is fasted or random on the request form.’

Professor Simon de Lusignan, who also authored the paper, added: ‘In many cases provenance information appears to be lost in the pathology lab process.

‘The primary care clinician thinks that they have made a request that includes the provenance of the test. However, what comes back with the result is a non-specific code.’

The study is published in Diabetic Medicine.









Readers' comments (8)

  • Why not ask for an HBA1C instead ? No fasting needed, and it pickes up different types of glucose intolerance.

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  • Apparently fasting tests for glucose and cholesterol are of no value and it is hba1c which counts

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  • @Monica Stevens - you do know HBA1C is not reliable if people of asian/african origin because of haemoglobinopathy and thalassemia. The issue here is people taking the blood samples need to identify is patient was fasting at the time the blood sample was taken.

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  • @5:24

    Isn't that why we use fructosamine?

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  • If you get an abnormal HBA1C That you suspect may not be reliable you can then do a glucose tolerance test.

    You will know that they have fasted for this.

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  • @Monica Stevens - would suggest you read

    I have not come across fructose mine testing. Hba1c is good to diagnosis and monitor diabetes in Caucasians. One of the main reasons it is not accepted globally is because of abnormal haemoglobin. The percentage of abnormal haemoglobin in Asians and Africans could be as high as 30 percent.

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  • I suspect this is a local laboratory issue. Running a Biochemistry lab - and during my training - there was always a distinction made between fasting and random glucose requests. We knew that the diagnosis of diabetes would be made on the basis of the fasting values.

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  • And if the patuent has any if the acute PORPHYRIAS, there is a risk of a life threatening attack, because of fasting!

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